code: def do_test_io():
      length_bytes = sys.stdin.read(4)
      if len(length_bytes) == 0:
          return False  # EOF
      elif len(length_bytes) != 4:
          raise IOError("I/O error")
  
      # "I" is "unsigned int", so this depends on running on a platform with
      # 32-bit "unsigned int" type.  The Python struct module unfortunately
      # has no format specifier for uint32_t.
      length = struct.unpack("<I", length_bytes)[0]
      serialized_request = sys.stdin.read(length)
      if len(serialized_request) != length:
          raise IOError("I/O error")
  
      request = conformance_pb2.ConformanceRequest()
      request.ParseFromString(serialized_request)
  
      response = do_test(request)
  
      serialized_response = response.SerializeToString()
      sys.stdout.write(struct.pack("<I", len(serialized_response)))
      sys.stdout.write(serialized_response)
      sys.stdout.flush()
  
      if verbose:
          sys.stderr.write(
              "conformance_python: request=%s, response=%s\n"
              % (
                  request.ShortDebugString().c_str(),
                  response.ShortDebugString().c_str(),
              )
          )
  
      global test_count
      test_count += 1
  
      return True
  
file_path: turicreate/src/external/coremltools_wrap/coremltools/deps/protobuf/conformance/conformance_python.py
imports: import struct
  import sys
  import os
  from google.protobuf import json_format
  from google.protobuf import message
  from google.protobuf import test_messages_proto3_pb2
  import conformance_pb2
label_desc: Use image node_id 2 for calling a global function with example usage: do_test_io() and returns: True, False